(CNN) -- While the Kennedy family waited Saturday for word on the fate of John F. Kennedy Jr., Kennedy-watchers were reminded of the twin clouds of controversy and tragedy that seem to perpetually surround America's most prominent political family, beginning with the son who was expected to be the political star.

Joseph P. Kennedy Jr., the eldest son of Joseph and Rose Kennedy, died in a plane crash in 1944 during World War II. He was 29.

Sister Rosemary Kennedy has been institutionalized since 1941 because of mental retardation and the effects of a failed lobotomy.

Kathleen Kennedy married William John Robert Cavendish, the Marquess of Hartington, who was killed in World War II. She later died in a plane crashin France in 1948. She was 28.

Joe and Rose took solace in their three surviving sons -- John, Robert and Edward -- but the family's tragic legacy followed them, too:

President John F. Kennedy, was assassinated in Dallas on November 22, 1963. He was 46.

His son Patrick was born prematurely in August 1963 and died two days later, three months before his father's assassination.

Robert F. Kennedy was assassinated in June 1968 as he campaigned for the Democratic party's presidential nomination. He was 42.

David Kennedy died in 1984 of a drug overdose

His son David died in 1984 of a drug overdose in a hotel after being ousted from the family vacation home at Palm Beach.

His son Joseph (Joe) was involved in a 1973 car accident that left a female passenger paralyzed for life. Now a Massachusetts congressman, Joe announced in 1997 he was dropping plans to run for governor. The same year, his ex-wife wrote a book criticizing him for asking the Roman Catholic church for an annulment.

His son Michael, who drew negative publicity for an alleged affair with his family's underage baby sitter, was killed on December 31, 1997, in a skiing accident in Aspen, Colorado. He was 39.

In 1969, aide Mary Jo Kopechne died when Edward Kennedy drove his car off a bridge on Chappaquiddick Island, off Massachusetts

The clan's surviving patriarch, Sen. Edward M. Kennedy (D-Massachusetts), drove a car off a bridge on Massachusetts' Chappaquiddick Island in 1969 after a party. The accident killed aide Mary Jo Kopechne, and controversy over the incident effectively ended the Massachusetts senator's presidential aspirations.

His son Edward Jr. had his right leg amputated in 1973 because of cancer; his son Patrick, now a congressman, sought treatment for cocaine addiction as a teen-ager in 1986.

His nephew, William Kennedy Smith, was accused of rape in 1991 at the family estate in Palm Beach, Florida. He was acquitted.